29.03.2017 18:53, Paolo Bonzini wrote:
On 29/03/2017 17:29, Dr. David Alan Gilbert wrote:
'abort' is not very good too I think. migration is completed, nothing to
abort.. (may be successful migration to file for suspend, some kind of
vm cloning, etc)
There is already migrate_cancel. Does it make sense to make it
reactivate fds if migration is completed?
It's potentially racy to do that.
Imagine if your migration is almost finished and you issue a migrate_cancel,
what happens?
Maybe it cancelled it.
Maybe it just completed in time - and you really better not be accessing
the disks on the source unless you're sure the destination isn't running.
If you want to avoid races, you probably have to use -S anyway on the
destination and do more handshaking between source and destination. But
yes, just to be safe it'd be better to add a new flag (-f for HMP,
'cancel-completed-migration':true for QMP or something like that).
Paolo
Looks like we haven't final conclusion on this (solve problems, noted in
patches 2 and 3). Are someone working on this now?
--
Best regards,
Vladimir
